<template>
  <div class="page-loadmore">
    <img id="scaleBackground" src="@/assets/images/01.jpg" :style="{ transform: 'scale3d(' + moveTranslate + ',' + moveTranslate + ',1)' }" alt="">

    <div class="page-loadmore-wrapper" ref="wrapper" :style="{ height: wrapperHeight + 'px' }">
      <mt-loadmore :top-method="loadTop" @translate-change="translateChange" @top-status-change="handleTopChange"       :bottom-method="loadBottom" @bottom-status-change="handleBottomChange" :bottom-all-loaded="allLoaded" ref="loadmore">

        <ul class="page-loadmore-list">
          <li v-for="item in list" class="page-loadmore-listitem">{{ item }}</li>
        </ul>


        <div slot="top" class="mint-loadmore-top">
          <span v-show="topStatus !== 'loading'" :class="{ 'is-rotate': topStatus === 'drop' }">↓</span>
          <span v-show="topStatus === 'loading'">
            <mt-spinner type="snake"></mt-spinner>
          </span>
        </div>


        <div slot="bottom" class="mint-loadmore-bottom">
          <span v-show="bottomStatus !== 'loading'" :class="{ 'is-rotate': bottomStatus === 'drop' }">↑</span>
          <span v-show="bottomStatus === 'loading'">
            <mt-spinner type="snake"></mt-spinner>
          </span>
        </div>
      </mt-loadmore>
    </div>
  </div>
</template>

<style scoped lang="scss">
  .page-loadmore{
    position: relative;
    overflow-x: hidden;
    top: 0px
  }
  #scaleBackground{
    position: fixed;
    top:0;
    left:0;
    width: 100%;
    height: 100px;
    z-index: 99999;
  }
  .page-loadmore-wrapper{
    padding-top: 100px;
  }


  .loading-background, .mint-loadmore-top span {
    -webkit-transition: .2s linear;
    transition: .2s linear
  }
  .mint-loadmore-top span {
    display: inline-block;
    vertical-align: middle
  }

  .mint-loadmore-top span.is-rotate {
    -webkit-transform: rotate(180deg);
    transform: rotate(180deg)
  }

  .page-loadmore .mint-spinner {
    display: inline-block;
    vertical-align: middle
  }

  .page-loadmore-desc {
    text-align: center;
    color: #666;
    padding-bottom: 5px
  }

  .page-loadmore-desc:last-of-type,
  .page-loadmore-listitem {
    border-bottom: 1px solid #eee
  }

  .page-loadmore-listitem {
    height: 50px;
    line-height: 50px;
    text-align: center
  }

  .page-loadmore-listitem:first-child {
    border-top: 1px solid #eee
  }

  .page-loadmore-wrapper {
    overflow: scroll
  }

  .mint-loadmore-bottom span {
    display: inline-block;
    -webkit-transition: .2s linear;
    transition: .2s linear;
    vertical-align: middle
  }

  .mint-loadmore-bottom span.is-rotate {
    -webkit-transform: rotate(180deg);
    transform: rotate(180deg)
  }

</style>

<script type="text/babel">
  export default {
    data() {
      return {
        list: [],
        allLoaded: false,


        bottomStatus: '',
        wrapperHeight: 0,



        topStatus: '',
        //wrapperHeight: 0,
        translate: 0,
        moveTranslate: 0



      };
    },

    methods: {
      handleBottomChange(status) {
        this.bottomStatus = status;
      },
      loadBottom() {
        setTimeout(() => {
          let lastValue = this.list[this.list.length - 1];
          if (lastValue < 40) {
            for (let i = 1; i <= 10; i++) {
              this.list.push(lastValue + i);
            }
          } else {
            this.allLoaded = true;
          }
          this.$refs.loadmore.onBottomLoaded();
        }, 1500);
      },
      handleTopChange(status) {
        this.moveTranslate = 1;
        this.topStatus = status;
      },
      translateChange(translate) {
        console.log('translate：'+translate)
        if(translate<0) return;
        const translateNum = +translate;
        this.translate = translateNum.toFixed(2);
        this.moveTranslate = (1 + translateNum / 70).toFixed(2);
      },
      loadTop() {
        setTimeout(() => {
          let firstValue = this.list[0];
          for (let i = 1; i <= 10; i++) {
            this.list.unshift(firstValue - i);
          }
          this.$refs.loadmore.onTopLoaded();
        }, 1500);
      },

    },
    created() {
      for (let i = 1; i <= 20; i++) {
        this.list.push(i);
      }
    },
    mounted() {
      this.wrapperHeight = document.documentElement.clientHeight - this.$refs.wrapper.getBoundingClientRect().top;
    }
  };
</script>
